concussion crisis in the nfl. A federal judge has rejected the $765 million settlement between the league and former players suffering head injuries saying that may not be enough to compensate everyone affected. Abc's ryan smith is tracking the case. Reporter: This morning the nfl's biggest blow yet, a judge stacking a $765 million settlement over concussion claims saying it may not be enough. U.S. District court judge anita brody saying "i have concerns about the fairness, reasonableness and adequacy of the settlement" demanding to see evidence of more than $750 million will cover the estimated 20,000 players and families over a 65-year period. Some of the nfl's biggest stars now seeing the light at the end of the tunnel like super bowl WINNING QUARTERBACK jim McMahon who has early stage dementia. I went through two strikes during my career and I was hoping that my medical bills would be paid for. You know, hopefully now they will be. Reporter: Relief also for the families of players like junior seau whose 201 suicide they say is due? Part to the big hits in the nfl. He loved the game, but I know that he didn't love the end of his life. Reporter: The current settlement had the promise of big bucks for some players including up to $5 million for players diagnosed with als and up to $3.5 million for players with diseases like alzheimer's and parkinson's. The judge fears the upon may run out. The league and players arpz attorneys unfazed by this development. The nfl saying judge brody's request for more information is a step towards preliminary approval while the players' attorneys say they are "confident" it'll get done. The judge says I want to satisfy myself the deal works and I want to say to the players, sit tight. This is part of the process. This deal will be approved. Reporter: Still, at the end of the day, the judges is the ultimate referee. The players can choose to opt out of the deal and file their own lawsuits but if too many do, the settlement could be in jeopardy so the question now becomes if the judge doesn't think the settlement is enough, will the players. George? A big question, ryan, thanks very much.

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